Component is understood to mean any device performing at least one function, electrical and/or mechanical and/or chemical, and comprising electrical interfaces.
An interconnection or pathway makes it possible to electrically connect, to the surface of the component, contact regions situated in one or more connection layers embedded at different levels.
In the known processes, interconnections or pathways are produced by successive stages, in a proportion of a stage of producing, through the substrates (or through an insulating layer, in the case where two interconnection layers are separated only by an insulating layer), passage regions, followed by a stage of filling the latter, for each interconnection layer, as the stack is produced, the interconnection layers being situated at different levels of the stack.
In other words, in the case of three connection layers, at least one passage region is produced for the conductive pattern or patterns of the first connection layer, which is filled with a conductive material in order to form an interconnecting section forming a portion of the interconnection.
Subsequently, for the second connection layer, there is produced, through an insulating layer which separates the first and the second connection layers or through the second substrate, at least one passage region for the conductive pattern or patterns of the second connection layer and also at least one passage region for extending the portion of the pathway towards the first connection layer, and so on for the third substrate.
Thus, similar stages are repeated several times during the manufacture, in order to produce the interconnections by sections, which increases in proportion the manufacturing costs.